My basic argument is that the end is near for the smartphone, in a number of ways. The shape, size, and design is mostly settled, and while smartphone companies are still cramming more technology into these devices, consumers are showing very little interest in that. We're pretty happy with the handsets we have and there's no new must-have feature on the horizon.

Consumers are also benefiting from a hyper-competitive smartphone market that's becoming saturated and commoditised, all of which means we can buy cheap but extremely powerful handsets. A $200 smartphone can do pretty much the same things as a $1,000 one.

This is great for us, but less great for the smartphone companies -- particularly the big brands wanting to charge a premium for flagship handsets. To be clear, we will still use our smartphones, and will for years to come. But, whether you like it or not, the economics of the smartphone market mean the tech giants are already searching for the Next Big Thing.

Parallel lines

What we would broadly call 'personal technology' is now evolving on two parallel tracks.

There's the ambient path, where computing and connectivity are embedded into the fabric of the world around us. Amazon's Echo (and Alexa) is an obvious example, but there's lots more on the way. Add 'smart' as a prefix to any physical object you can think of, and someone will already be working on a version of it.

Cars, washing machines, toothbrushes, light bulbs, shoes, and your front door will all have soon some kind of intelligence built-in, which will allow you to interact or control them digitally. But each of these interactions are fleeting and therefore of relatively low value.

That could play to the strengths of some companies, but not others. And if the smartphone is to become just one device among many, what does that do to the business models of some of the world's largest tech companies, where the rising profits demanded by investors can only be generated by knowing more and more about us?

Will augmented reality smartglasses replace the smartphone?

Microsoft

That's where the second and more controversial path comes in -- the one I think is heading back towards smartglasses.

You see, I struggle with the idea that the smartphone is the complete and final incarnation of the gadget that we will carry around with us.

Just because it is right now, there's no reason why it should be forever. Predicting the future is always fraught with risk -- but predicting the end of history has an even worse track record.

A lot of the comments on my original column were very hostile about the idea of smartglasses, arguing that smartphones are exactly what we need. That reminds me of the line attributed (with little evidence) to motor mogul Henry Ford: "If I'd asked people what they wanted, they would have said faster horses."

It reminds us how we are rarely the best judge of products that don't yet exist, because we see the future through the prism of what we know and use today.

A decade ago, many were sceptical about the usefulness of smartphones and smartphone apps, and even further back I can remember the scorn poured on the first mobile phones.

The case for smartglasses

Since I wrote my original 'death of the smarpthone' column, I've been paying more attention to the situations in which some kind of smartglasses -- I'm imagining something like a pair of sunglasses with the ability to display real-time information as an overlay on the real world -- could prove handy.

Far from being a niche device, I can see plenty of use cases that would allow me to unobtrusively access information (How fast am I cycling? What time does that shop open? What's his name?) without the need to dig into a pocket for a phone (and then likely walk into a lamppost while fiddling with it).

Smartglasses could make it much easier to consume some of the vast amounts of information that flow around us at all times. They wouldn't be appropriate in every situation -- but then again, neither is a smartphone today.

Tech companies -- especially those that generate their profits from advertising -- would benefit hugely from this evolution, which is of course why they are working on it right now.

Just think about the vast amounts of data that our gaze creates -- who we meet, what we linger on, and what we ignore. It's as intimate as possible without a direct link to our brains (which tech luminaries are working on too, of course).

There are big hurdles ahead, before smartglasses would be able to take off. I can't think of a more intimate level of interaction between humans and gadgets than letting them share what we see. All of the unresolved privacy issues of the smartphone age will have to be revisited, too.

Many, including myself, would be extremely cautious about using smartglasses -- especially if they create a physical barrier between me and those around me. And I don't want to talk to someone wearing a video camera on their face, either.

But for coming generations more used to being connected than disconnected, such devices will make a lot of sense. You may never wear Snap Spectacles, or use an Oculus Rift, or don a HoloLens for work -- but your kids might.

It's by no means certain that this Next Big Thing will be successful; certainly the first smartglasses were distinctly lacking in pretty much every way: limited functionality, poor battery life, and the infamous 'Glasshole factor'.

None of these have been resolved, but none of them will stop tech companies from trying again.

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